Roving frame



May 1, 1945. ca. E. REPASS 2,374,332

ROVING FRAME Filed Dec. 1, 1942 7 Sheets-Sheet l mvsiuron George E. Reposs ROVING FRAME Filed Dec. 1, 1942 7 Sheets-Sheet 3 n2 I I 35 lol INVENTOR BY George E.Reposs j ATTORNEY y 1945. G. E. REPASS ,8

ROV IN G FRAME Filed Dec. 1, 1942 7 Sheets-Sheet 4 INVENTORI BY George EReposs ATTORNEY May 1, 1945. G. E. REPASS 2,374,832

ROVING FRAME Filed Dec. 1, 1942 7 Sheets-Sheet5 IOI 4 INVENTOR 7 BY GeorqeERepcss 3 ATTORNEY y ,1945. G. E. REPASS 2,374,832

I ROVING FRAME I Filed Dec. 1, 1942 7 Sheets-Sheet 6 INVENTOR Ll George E.Reposs BY U a ATTORNEY G. E. REPASS ROVING FRAME May 1, 1945.

Filed Dec. 1. 1942 7 Sheets-Sheet 7 w R R n O.N m m w w m m Patented May 1, 1945 ROVING FRAME George E. Repass, Pawtucket, R. 1., assignor H & B American Machine Company, a corpor tion of'Maine Application December 1, 1942, Serial No. 467,489

8 Claims. .(Cl. 57-96) v This invention relates to roving machines, and more particularly to that portion of such machines by which variable rotary motion is given to the spindles and their bobbins and a variable traversing motion is given to the lifter rail upon which the bobbins are carried.

Roving machines as heretofore constructed have usually been provided with a variable speed, driving mechanism for driving the spindles andthe bobbins carried thereon at variable speeds comprising two relatively long a tapered cone drums disposed one above the other and con-;

nected by a driving belt which. is advanced along the coned surfaces of the drums upon reversal of the lifter rail at the end of each traverse of the lifter'rail so that the speed of the bobbins changes automatically and simultaneously with the reversal of the lifter rail at theend of each layer of material wound on the bobbins. The top or driving cone drum usually is formed with a concave surface and driven at constant speed from the main shaft of the machine. A gear train from the top cone drives the drawing rollers of the machine, the front pair of rollers of which deliver the attenuated textile material to the.

flyers associated with the bobbin spindles. v

'ThfigbOttOlIl or driven cone drumusually is formed ,with a convex surface and partakes of a variable rotational speed during the shifting movement of the cone belt longitudinally of the cone drums from one end to the other that aceter, the product of bobbin diameter andwinding'revolutions remaining constant. The gearing is so arranged that the variable rotary motion of the bottom cone drum driving through an epicyclic gear train, known as a diiferential motion,

regulates'the winding speed of the bobbins to give them thenecessary winding speed as the bobbins increase in diameter.

' This prior and normal method of drive of the roving frame bobbins at variable winding spee s although satisfactory 'insofaras accomplishing the necessary variable regulation of the bobbin winding speed, nevertheless isfound to, possess certain objectionable features. which frequently introduce serious defects in the quality of the roving on the bobbins, as is well known. For example, non-uniform or improper tension of yarn from the front drawing rollers to the bobbins frequently occurs due to slippage of the cone beltduring its advance along the cone drums. Also, this method of drive invites tampering with the setting of the tension mechanism by the roving machine operator instead of making the correction of the tension at the twist gear. Fur-' thermore, the cone drums are bulky and occupy considerable valuable space within the framework of the machine, and areof expensive construction. 7

It is accordingly an object of the present invention to provide an improved variable speed driving mechanism that will take the place of the aforementioned concave and convex cone drums and will serve the same, purpose as such prior mechanism. without its disadvantages.

Another object of. the invention is the provision in a roving frame organization of a variable speed driving mechanism including driving and driven expandible pulleys connected together by a V-belt, each pulley being formed of a pair of conical members one of which is fixed and the other shiftable, and a control cam connected to the shiftable member of each pulley in which the arrangement is such that the control cam is revolved intermittently by the rack gear of the builder motion and willbe actuated simultaneously with the reversal of the lifter railand the shorteningof the traverse of the lifter rail whereby the shiftable members of both pulleys will be automatically adjusted together to vary, step by step, the eifective diameters of the pulleys so as to decrease the speedoi rotation of the bobbins as their diameters increase.

A further 'object of the invention is to provide in a speed varying organization of the abovedescribed character a control cam which is so shaped and arranged as to regulate the effective diameters of the expandible pulleys to produce the same speed variation effect on the bobbins as that obtained by means of the concave and convex cone drums which is the common speed varying device in roving frames for driving the bobbins and their carriage.

A still further object of the invention is to provide in a variable speed driving mechanism of the above-described character, novel arrangements :of elements which will provide a simple and compact construction capable of being manufactured at small cost, which will result in emcient operation, and which will reduce to a minimum any possibility of wear which might result in uneven or improper operation of the various elements of the mechanism. 3 With these and other objects in View, the invention consists of certain novel features of con- In the accompanying drawings: I

Fig. 1 is a front elevation of so much of the each other and driven one from the other and J receiving their power through a chain and sprocket drive 24 from the main drive shaft 25 operative portion of one common type of rov: ing frame as is necessary to illustrate the nature of the present invention and its relation to the usual operating parts of the'mechariism'forvarying the speed of the bobbins andthe builder" motion;

Fig. 2 is a front elevation on a larger scale, than Fig. l of the portion of the roving frame.

position to slacken thedriving belt connection and render inoperative the upper driving expandible pulley; l. i

Fig. 4 is a-detail view, partly iii-section; showing the arrangement and construction of the expandible pulleys and the cam mechanism associated there-with for moving the s'hiftable wheel members of each pulley; Y

Fig. 5 is a view takenion the line 5-5 of 'Fig. 4; Fig. 6 is an end view of one" ofthe conical wheelsof an expandible pulley;

Fig."1 is a detail view, observed from the underside, of the cam. for imparting the variable adjusting motion to both shiftable wheel mem-,

bers of the expandible' pulleys forkvarying th speed of the bobbins; v i

Fig. 8 is a vertical section taken on the line 8-8 of Fig. 3 showing the gearing connecting the lower eXpandible motion; and i Fig; 9- is a diagrammaticview of the gearing incorporating the expandible pulleys of the pres ent invention by which variable motion is imparted to the bobbin spindles and tothe lifter rail carrying the bobbins. I

As the general construction and operation of roving frames 'or speeder'sare well known and familiar to those skilled inthe art it will be necessary hereto illustrate and describe only the elements of the machine directly concerned with the present invention. l

In the drawings, wherein for the purpose of illustration is shown a preferred-embodiment of the invention, there is represented one common type of roving frame or speeder-the general arrangement oi which is shown in Fig. l an comprises termediate samsons H, and the roller beam-l2 which extends longitudinally of the machine at the front of the latter and is attached to the fixed framework of the machine. v

Bobbins 14, of which only one'is'shown in the presentdrawings, rotatably'mounted on thelifter rail or carriage I5 aregiveha rising-and-falling motionin the. usual and well-known manner between .the depending arms and l1--of' the ri er's l8 which are suitably attached to the top of th'elon'g upright spindlesl9. The lifter rail l5'in ractice extends longitudinally of the 1 1 3" to the differentialone of the machine end frames 10, iii-- machine for substantially its entire length, and carries thereon the usual fixed bolsters (not shown) and the short loose sleeves (not shown) that surround the lower end of the bolster, all of which structure is common and well known in the art.

The spindles 19 are driven by the bevel gears 20 and. 2| thatreceive power from a long spindle snail-.22 running the: whole"v length of the machine. There are two lines of upright spin- .dles l9 and twospindle shafts 22 parallel to a Power is transmitted from a motor 21 to the pulley 26 1 by means of a multiple V-belt sheaved pulley 28 pnthe motor shaft and a plurality of V- belts connecting the pulleys 26 and .28. The main. drive shaft 25 transmits rotary motion through the gears 30, 31-, 32 and 33 to the, upper horizontalshaft vi5 for driving one of the expandible pulleys of the variable speed driving mechanism of the present invention as will be more fully described hereinafter, an from the gear 33 through the gear :36 to drive the lower front fluted drawing roller 31. The lower middle and back drawing rollers 38 and 39 are arranged parallel to the front roller 31 and are driven therefrom by suitable gearing in a mam her well known in the art.

The bobbins M are driven *through beveled gears 40 and 4| and by silent chains 43 and 44 from a sleeve 45 which turns loosely on the main drive shaft '25. The sleeve 45 is driven from the shaft 46 through the differential-motion 41 and the gear train composed of gears 48, 49 and the .pinion5l attached to the shaft 46. The

40 shaft '46 is given variable rotary motion by the which is given an upward and downward motion by'a rack 55 and a pinion 56 fast one shaft 51.

The shaft 51 is driven through the intermediate shaft 58 and connecting gearing from the shaft 60 on which are aflixed the elongated spur gear 6t and the beveled-gears 52 and '63 which arealternatelybrought into engagement with the beveled pinion 64 on one end of a shaft. The

variable rotational motionof the shaft 46 also is transmitted to the shaft 65 whichv is driven through the gear 50' meshing with gear 49,.gears 66- and 61. and bevel gears-68 and 69 from-the pinion-5| -on.the shaft lfi. a

When the 'bevel gear 62 .is-inxengagement with the bevel gear 54, the traversing-bobbin rail 15.

will be moved in one direction,v and when the bevel gear 6-3 is in engagement withthe bevel gear 64 the rail will be moved in an opposite direction, and the-alternate engagement of 'the bevel gears 62- and 63 with the bevel gear 64, is

accomplished by longitudinally sliding the shaft 611 backwards and forwards in. its. bearings. by

means of the slidingbar 1| and fo'rksi12 engaging collars 13 attached to the shaft 60.. The slid- -ing bar 'H is moved by areversing mechanism (generallyindicated at 15) by which the movement of the bar H is automatically reversed when thebobbin lifter rail 15 has reachedthe limit of its highest or lowest movement. Reversing.

mechanisms of various kinds arein common use,

in roving machines of this class and are ofwell known construction to those skilled in the art,

and as the traversing mechanism per se forms; no part of the present invention it is thereforeflyer speed is constant, the surface velocity of the.

bobbins must also be constant, that is, thewinding point on the bobbin must always be maintained a certain distance in advance of the foot of the .fiyer. As yarn is wound upon the bobbin its size is increased and it becomes'necessary to correspondingly decrease the speed of the bobbin sothat the yarn will not be wound upon the bobbin any faster as the bobbin fills with yarn and increases in size since the sliver is delivered at a uniform speed from the front rolls and therefore the surface speed of the bobbin must be exactly the same under all conditions as the surface speed of the delivery rolls in order to take care of the sliver as fast as it is delivered from the frontrolls. It is evident also that the yarn must be wound on the bobbin at uniform speed inorder to maintain a uniform, tension in the twisted yarn. To accomplish these objectives, it is necessary to gradually reduce the number of revolutions of the bobbin as it fills with yarn, andrthis is brought about through thedifferential motion 41 which, in the past, has been driven by one of the cone drums of the aforementioned prior speed-varying mechanism but, in the present instance, is driven at variable rotational speeds from one -of the expandible pulleys of the variable speed drivingmechanism of the present invention hereinafter to be described. i

. As previously mentioned, the reduction of the speed of the bobbin as its diameter increases has heretofore been accomplished by the employment of two cone drums .connected by a belt' which is moved along the drums by means of a rack-andpinion mechanism actuated by a vertical shaft the rotation of which is efi'ected by a weight so that the rotation of this shaft will cause the belt which-connects together the two conical drums to be pushed along from the larger to the smaller end of the driving'drum. It has been found necessary in practice to make one of the drums with its periphery slightly concave and the other drum with its periphery slightlynconvex in order to secure the requisite variation in the speed. of the driven drum.

In accordance with the present invention I'pro-.

vide a novel variable-speed driving mechanism for automatically varying the speed of thebobbins comprising two expandible pulleys arranged one above the other-on parallel shafts and connected by an edge active driving belt whereby power will be transmitted from one shaft to theother.

further feature of the invention. comprises means I suffice forthe other.

including a cam for automatically operating the shiftable pulley elements to simultaneously vary the. effectiveworking diameters of the pulleysv and this cam is so constructed andarranged that the same variation in the speed of the driven expandible pulley willbe secured and communicated to the bobbins as that now obtained by the usual. concave and convex conical drums in pres:

ent type roving machines. v

, In the embodiment illustrated the variable speed. driving mechanism is shown ascomprising thev expandible pulleys generally designated 8|!v and8l which are mounted inan operative-relation on the parallel shafts 35 and 46 respectively. The expandiblepulleys and 8|, are of similar. construction 50 that the description of one will Referring particularly to Fig. 4 of the drawings, the expandible pulleys are shown as being composed of two wheel members 83 and 84 each of which is substantially, frusto-conical in shape with their conical side faces arranged in confronting relationship and slotted longitudinally to provide the tapering peripheries of thewheel members with a series of fingers85 separated by open spaces 86 (see Fig. 6). The fingers 85 are rigidlyconnected to the annular rim or base 81 of each wheel member. The wheel members 83 and 84 of the respective. pulleys, B8. and 8| are mounted on the shafts 35 and 4.6. respectively with the fingers 84 of one wheel. member entering and having.interengag-; ing relation with the slots88 of the opposite wheel, coupling the wheel membersof each set together when they are telescoped together during their operation, as hereinafter described.-

The wheel members 83 are fixedto theirrespective shafts 35- and 46, and the wheel members'84 are slidably arranged so as to be shift:- able thereon toward and away from the fixed wheel members 8 3 so that by moving the wheel memberv 84 along its particular shaft, the effective working diameter. of the expandible pulley -may vbe increased or diminished. The

"expanding pulleys .88 and 8| are shown connected together by means of an edge active driving belt 88 which may be V-shape in cross section to. provide suitable side friction faces for; engaging. the confronting conical faces of the wheel. members 83 and 84 of each expandible pulley. Inorder to adjust the. diameters .of the expandible pulleys. 88 and 8| automatically whereby the same variationin speed of driven pulley BI is secured as now obtained by the usual.

concave and convex cone drums aforementioned, provision is made for automatically operating the expandible pulleys simultaneously and in response to the change in the direction of traversev of the bobbin rail at both extremes of itsstroke.

This is accomplished by moving the shiftable. I

wheel member 84 of the upper expandible pulley 80 awayfrom the fixed wheel member 83 thereof so'as to increase the gap of the V-groove formed by the conical sides of these two wheel members and enable the V-belt88 to descend more deeply therein. Simultaneously with this widening action of the two wheel members of the upper expandible pulley 80 there occurs a decreasing in the gap between the confronting conical sides of the two wheel members 83 and 84 of the lower,

expandible pulley8l.

The shiftable wheel members 84 of the upper and lower expandible pulleys 88 and 8! respectively are connected by arms 90 and 9| .to a horizontal slide 92 which is suitably arranged for longitudinal reciprocation in the, samsons II of the frameworkof the machine. The two shiftable wheel members 84 are movedtog'ether inthe same direction by the reciprocation of the} slide 92which is actuated by means of a cam 95 fastened to the underside of a gear 96. The

cam 95 is slotted as indicated at 91 (see Fig. 7) and connected with the slide 92 by a pin 98 which is fixed in a bracket 99 attached to the slide 92, and the pin 98 projects into the slot 91 of the cam through an elongated slot 99' formed in a horizontal plate member I which is positioned above the slide 92 out of contact therewith and suitably secured to the upright channel |0| of y the framework 'of the machine. The cam 95 and its associated gear 96 are rotatably mounted upon astud I02 secured to the plate member the vertical shaft I05, and both the reversing and escapement mechanisms are in common use in roving frames, and they are therefore not described herein in detail, as they form no part of .the'present invention other than providing the automatic control means for intermittently operating the expandible pulleys.

7 builder motion-becomes operative. which is at both ends of the-stroke of the bobbin rail I5 to produce shortening of the layer. Furthermore,

the finger I I5'forming the stop for actuating the automatic stopping mechanism of themachine is suitably secured to the gear 96 (see Fig 5); and capable of'manual adjustment about the stud I02 for positioning in different angularly' adjusted positions where it may become effective at various selected positions during the rotationofthecam All the operative mechanism between the' bobbin I4 and the differentiall'l together with the-reversing mechanism by which the shaft 00 is: moved back and forth in order to reverse the motion of the traversing rail I5, the vertical shaft I I0 carrying a drum I I2 acted upon by the weight I08 and the escapement mechanism I06. connected therewith, are already in common use and well known, and their construction and operation will be,clear1y understood by all who' are conversant with machines of this class.-

In Fig. 7 the slot 91 in the cam 95 is so shaped in its longitudinal extent that the intermittent and progressive rotation of the cam in moving the pin 98 from one end to the other of the slot 91 will produce a varying adjusting movement of the slide 92 and the shiftable wheel members 84 of the expandible pulleys 80 and 8| soas to secure the same variation in the speed of the bobbin I4 as now secured by the usual concave and convex cone drums of the common variable speed mechanism generally employed for this Purpose.

When the winding cycle is completed, the machine is stopped which action is effected automatically by an upright finger II5 adjustably mounted on the gear 96 and movable therewith as the gear rotates whereby the finger will strike the arm II6 of the pivoted lever II! which will be rocked to cause its other arm HR to push the locking piece I20 of the stopping mechanism sidea wise sufliciently to disengage the tooth |2I there of from the marginal portion of a slot I22 formed in the plate member I00 whereby the locking piece I20 thus released will drop through the slot and setin motion the automatic stopping mechanism of the machine. I

It is to be understood that the control cam 95 for regulating the expandible pulleys 80 and BI to effect a change in speed of the bobbins is revolved intermittently to impart step-by-step movement of the slide 92, so that operation of the cam 95 occurs only during the period when the 'Means' are provided'whereby the operator mayrender inoperative the belt connection between the expandible pulleys and 8| manually at any time during the operation of the machine, and without stopping the machine, when eitherthe filling of the bobbins is completed orwhenever it is desired to stop the rotation of the bobbins during winding. In Figs. 2and 3 there is illustrated in detail my preferred means for attaining the above-mentioned result, in which instance, the lower shaft 46 together with the expandible pulley 8| thereon is lifted bodily from its" normal working position as shown in Fig. 2 and held in an elevated and inoperative posi tion shown in Fig. 3 thereby disengaging the driving connection of the V-belt 08 with the coned wheels 83 and 04 of the'lower expandible pulley so that the belt 88 will run slack and no drive of the pulley 8| thereby willtake place. Referring'now to Figs. 2, 3 and 5, it will be seen that the shaft 46 carrying the expandible pulley 8| is suitably journaled in bearing stands I25 which are mounted for pivotal movement vertically and suitably attached to the framework of the machine. As illustrated in Fig. 5, the bearing stands I25 (which, in the present embodimentwof my invention, comprises twomembers of which only one is illustrated in this figure) is mounted at the outer endof arms I26 whichare'attached by brackets I21 loosely mounted for pivotal movement on a horizontal rod I28 fixed at its' opposite ends in brackets I29 suitably-attached to uprightframe elements of the machine, the rod I28 providing the pivot for the arms I26 being positioned behind and parallel to the shaft.

A cam I30 is keyed, pinned or otherwise secured to the lower end portion of a vertical shaft I3| journaled in the brackets. I32 and I 32'-.. The

cam I30 consists of a curved platespaced from shaft I3I 'andformed with a'reversely curved sl'ot' I33 which is shown as being obliquely disposedwith respect to theaxis of the shaft I3I. A cam roller I34 extends into and cooperates with the slot I33, the camroller I34 being suitably mounted for free rotationon the outer end por-' tion of a finger I35 which projects forwardly from and is attached to the underside of the arm I26 supporting the bearing stand I25 proximate to the shaft I3I.

I30 preferably is so shaped and disposed as to produce rapid raising of the shaftv 46 and its associated pulley 8| during movement of the cam roller I34 through the longitudinal'extentof the inclined portion of the slot -|'33.- The slot I33 terminates. at its upper end in a notch I36 into which the cam roller I34 enters for holding the shaft 46 and its associated pulley 8| in elevated position. Manual movement of the shaft |3I by' the operator in the opposite directionwill force the cam roller out ofthe notch I36; thence downtheslot' I33 to the bottom end thereof to lower'the shaft *46 and theexpandible pulley BI- and .establish driving connection of the pulley 8| withthe V-belt 80. 1 .V

The slot I33 in the camf In the embodiment illustrated; and" described above, the parts-are so arranged-that whenthe bobbin rail is in its lowest'position the wheel sections of the lower expandible pulley 8l"wil1 be fully telescoped, while those of the upper expandible pulley 80 will be open to provide expansion. Furthermore, as progressive shortening of the strokeof the rail takes place due tothe action of the usual builder'motion there also'occurs 'simultaneously therewith "changesin the bobbin speed so as to produce the same'lineartake-up on the bobbins as is obtained when'the bobbin packages were of smaller diameter. V

In accordancewith the present invention'many advantages are obtained over the use of previous mechanisms employing'the concave'and'convex conedrums, among'which advantages are the following: (1) maintenance of uniform tension of (3) no stoppage of the V-belt connecting the two expandible pulleys for driving the lower pulley from the upper pulley; and (4) less Wear on this v-belt connection since it is of the edge-active type "Iclaim: i

1. In a roving frame, the combination with the bobbins of the machine of a variable speed mechanism'for driving'said bobbins comprising driving and driven expandible 'pulleysdisposd in spaced relationshipone above theotherj-"each of said expandible pulleys consisting of two 00- operating wheel members one of which is fixed and the other shiftable toward and away from said fixed wheel member, the wheel members forming each pulley being connected together in all positions of adjustment of the shiftable wheel member, an edge active belt providing a driving connection between said expandible pulleys for driving one pulley from the other, a slide, connections between said slide and the shiftable wheel member of each expandible pulley, means including a cam actuated intermittently by the usual builder motion of the machine and operable only during the reversal of stroke of the traversing bobbin rail in the opposite direction for moving both of said shiftable wheel members simultaneously relative to their associated fixed wheel members to vary the speed ratio between said driving and driven expandible pulleys, and intermediate connecting mechanism whereby the rotation of said driven expandible pulley is communicated to the bobbins .of the machine.

2. In a roving frame, the combination with the bobbins of the machine of a variable speed mechanism for driving the bobbins comprising driving and driven expandible pulleys each consisting of two coacting conical wheels one of which is fixed and the other shiftable axially toward and away from the fixed wheel of the set, the confronting sides of the opposed wheels being so constructed and arranged that the wheels of each pulley have interlocking and telescoping connection in all adjusted positions of the shiftable wheel members, a belt providing a driving connection between said pulleys, intermediate connecting mechanism between said driven expandible pulley and the bobbins of the machine, a slide, connections between said slide and said shiftable wheels, a rotatable cam operatively connected to said slide for actuating the same, and means responsive to the step-by-step adjusting movements of a builder motion of the intermittent type for revolving said cam to effect step-by-st'ep adjustment of-s'aid slideth'rough a distance suificien't to adjust the 'shiftable-wheels'of both expand ible pulleys, .r I L '3; In 'a' roving frame, the combination with the bobbins" of the machine of a variablespeed'mechanismior driving the bobbinsbomprising driving and driven expandible pulleys each consisting of two coacting'conical wheels'one o'f-which isfixed andthe other shiftable axially toward'and away from the'fixed wheel of the set, the "confronting sides of the opposed wheels beingso constructed and arranged that the wheels of each pulley have interlocking'and telescoping connection in all adjusted positions of the shiftable' wheel members; a belt providing a driving connection-be tween said pulleys, intermediate connecting mechanism between" said driven expandible pulley and the bobbins of the machine; a slide, connections between said slide and said shiftable wheels, a rotatable cam operativelyconnected ,to saidslide for actuatingthe samega gear afiixed'to said cam; and means'including'a pinion me'shing with said gear responsive to the step-by-step adjusting movements of a builder. motion of" the intermit tent'type for revolvingsaid cam to effect step? by-step adjustm'ent of -said slide through a dis tance sufiicient to adjust the shiftable wheels of both expandible pulleys. v 4. In a roving frame','the combination with the bobbins of the machine of'a variable speed mechanism for driving the bobbins comprising driv-' ingand driven expandible pulleys eachconsist- I ing of two interfitting conical wheel members one of which is stationary and the other slidable, a V-belt providing a driving connection between said pulleys, a pivoted support sustaining one expandible pulley, a slide, arms connecting said slidable wheel members to said slide for moving both slidable wheel members together when said slide is advanced to vary the working diameters of both expandible pulleys simultaneously, and means including a cam for imparting intermittent step-by-step adjusting movement in thesame direction to said slide to regulate the effective Working diameters of both of said expandible pulleys.

5. In a roving frame, the combination with the bobbins of the machine of a variable speed mechanism for driving the bobbins comprising driving and driven expandible pulleys each consisting of two interfitting conical wheel members one of which is stationary and the other slidable, a V- belt providing a driving connection between said pulleys, a pivoted support sustaining one expandible pulley, a slide, arms connecting said slidable wheel members to said slide for moving both slidable wheel members together when said slide is advanced to vary the working diameters of both expandiblepulleys simultaneously, and means including a cam for imparting intermittent step-by-step adjusting movement to said slide to regulate the efiective working diameters of both of said expandible pulleys, one of said arms being swingable .on said slide laterally of the slidable wheel member, said swingable arm being bifurcated and having a loose connection with the slidable wheel member to permit adjustment of the lower shaft, and means including a cam manually operable for raising said lower shaft and the expandible pulley thereon from an operative position to an inoperative position, and vice versa, to effect the disconnection and connection of said driving belt with the lower expandible pulley.

6. In a roving frame, the combination with the bobbins of the machine of a variable speed-mechanism for driving said bobbins comprising driv-l ing and driven expandible pulleyseach formed of two wheel sections one of which isv fixed and the other wheel section shiftable toward and,

away from the fixed wheel section, a belt providing a'driving connection between said expand-y ible pulleys, a cam, means for intermittently actuating said cam to produce step-by-step adjust ment of both shiftable wheelsections simultaneously relative to their respective fixed wheel sections to vary the effective working diameter of;

the pulleys and regulate the speed ratio therebetween, and intermediate connecting mecha nism whereby the rotation of said driven ex-,

pandible pulley is communicated to the bobbins of the machine. I v g 7. In a roving frame, the combination with the bobbins of the machine of a variable speed mechanism-for driving said bobbins comprising driving and driven expandible' pulleys each formed of two wheel sections one ofwhich is fixed and the other wheel section shiftable toward and away from the fixed wheel section, a belt providinga driving connection between said expandible pulleys, means for adjusting'both shiftable wheel sections simultaneously relative to their respective fixed wheel sections to varythe effective working diameter of the pulleys and regulate the speed ratio therebetween, intermediate connecting mechanism whereby the rotation of said member and operable thereby upon rotation of saidcam toazpredeterminedposition for actuate ing the automatic stop-motion mechar'iism of the machine. v a A ,8. In a roving frame, the combination of, two

- parallelshafts, one a driving shaft and the other operatively. connected to said slide for actuating driven expandible pulley is communicated to the bobbins of the machine, a cam, a stop member on said-cam, and means engaged by said stop I this purpose. 3

the .same, means operable by the ,usual builder motion of the machine .for intermittently operating said cam to produce step-by-step adjust-Y 'ment of said slide for adjustingthe working diameters of the'shiftable wheels of both expandible pulleys, and intermediate connecting mechanism whereby the rotation of said driven expandible pulley is communicatedto the bobbins of themachine, said rotatable cam being so shaped as-to secure substantially the same variation in the rotational speed of the bobbins that has been produced previously by the use of the prior convex and concave cone drums usually employed for GEORGE E. REPASS. 

